Abstract

In the study, we modelled population dynamics of the reintroduced Dinaric lynx population. We used data obtained by monitoring to estimate population dynamics – spatial expansion, abundance estimates, and mortalities – since the reintroduction in 1973 and up to the present day, and then looked for demographic and habitat parameters that would provide the best fit of a lynx population model to this data. We tried to evaluate the importance of these parameters for future population dynamics and viability (PVA) of this lynx population. We constructed a number of 100-year simulations using a range of demographic parameters, different prey availabilities and simulating other potential human related factors that might affect the lynx population. We found that the reintroduced lynx population must have had high fecundity rates with more than 1.6 kittens survived per female and per litter to reach abundances over 100 individuals despite the high human related mortality. The elasticity analysis revealed that adult survival is by far the most important demographic parameter for the lynx population dynamics. PVA highlighted two important factors that had a major impact on population growth dynamics and related risk of population extinction: changes in the survival rates of subadult and adult individuals and, especially, the quality of habitat with regard to prey availability. Survival rates of subadult and adult lynx are directly influenced by human activities, mainly manifested through illegal shooting, and are difficult to control. Quite opposite to that, the quality of habitat with regard to prey availability can be directly influenced through management. Since habitat quality can have a significant role for the lynx population dynamic and viability, even in presence of minor, difficult to control changes in survival rates of subadults and adults, adequate prey species management might be one of the most important short-term conservation priorities.

Keywords

Eurasian lynx, Lynx lynx , population dynamics, PVA simulation, reintroduction, Dinaric region

Abstract

The oxidative metabolism in animal tissues can be conveniently monitored by measuring tissue P O2 with a carbon fibre microelectrode. We have established a recording configuration in a living animal by insertion of a carbon fibre electrode (CFE) into the retina of a blowfly ( Calliphora vicina – chalky). The current flowing over an exposed carbon disc at the tip of an insulated carbon fibre with 5 μm diameter is linearly proportional to P O2 when the P O2 was varied between 0 kPa (100% N 2 ) and 100 kPa (100% O 2 ) in the recording chamber. The slight changes in sensitivity of CFE during the recording time were corrected by calibrations performed at the start and at the end of the experiments. Exposure of the eye to bright light caused a drop in tissue P O2 . Hypoxia increased with the stimulation time, reaching a maximum after about 20 s (Δ P O2 =11.6 kPa). These results are in good agreement with direct measurements of O 2 consumption in isolated eyes.

Keywords

blowfly eye, Calliphora vicina – chalky, carbon fibre electrode, P O2 measurement, amperometry

Abstract

Phalangium opilio is the most widespread and one of the most common harvestman species in anthropogenic environments. A preliminary field experiment was carried out in Slovenia testing its preferences for different substrates. A two metres high rectangular tower with walls constituted of vertical bands of concrete, twice fired tile, wood and styrofoam was placed in a meadow. The wood proved to be the most suitable substrate, providing the most stable temperatures and moisture levels in comparison with the other experimental materials. In anthropogenic environment, various available substrates in microhabitats of Ph. opilio considerably contribute to a fine regulation of searching relatively thermally and moist-stable resting sites.

Keywords

harvestman, arachnids, Arachnida, Slovenia, substrate preference, synanthropy

Abstract

The presence of the cyanobacterial bloom of Microcystis viridis (A. Braun) Lemmermann is reported for the first time in Slovenia. After field sampling, and detailed microscopic observations, species analysis, chlorophyll content analysis, and cyanobacterial cyclic peptides were determined, the latter by high performance liquid chromatography (HPLC). Cells were found in colonies with limited amounts of more or less refractive mucilage. The average diameter of a cell was 4–7 μm. Three microcystins, two anabaenopeptins and planktopeptin BL 1125, were identified. The content of cyclic peptides in the bloom was in the range of 2.3–6.6 mg g –1 of cellular dry weight. M. viridis was dominant in the cyanobacterial bloom, other species being Micorcystis wesenbergii, Microcystis aeruginosa, Anabaena flos-aque, Anabaena spiralis, Aulacoseira granulata, Closterium sp. , Euglena sp ., Pediastrum duplex, Scenedesmus quadricauda, Staurastrum gracile, Trachelomonas volvocina, Trachelomonas hispida and Tetraedron limneticum. In keeping with previous studies the content of cyclic peptides in the cyanobacterial bloom was high enough to cause bloom lysis. This fact was also confirmed by field observation; not only bloom composition change, but after 8 days there was no visible cyanobacterial bloom on the Boreci reservoir surface, although no heavy rain or wind was observed during this period. The discovery of M. viridis bloom in Slovenia is very important, since toxic bloom constitutes a threat all over the World.

Keywords

cyanobacteria, cyanobacterial bloom, Microcystis viridis , microcystin, cyclic peptides

Abstract

For several years now, Slovenia has been facing a shortfall of interest in science studies. Some argue that the principal reason for this lies with inadequately trained science teachers in primary and secondary schools. We set out to find the reasons why double degree students of biology (Chemistry-Biology or Biology-Home Economics) at the Faculty of Education chose to become biology teachers, and outline certain guidelines for pedagogical work with students. The results of our survey show that the number of secondary school graduates whose first choice is either of the two biology teacher study programmes at the Faculty of Education is declining. Students who selected the programme as their second choice are mainly those who did not have enough credit points for their first options, i.e. medicine, dentistry, biochemistry, veterinary sciences or biology at the Biotechnical Faculty. Most of the students who decide to become biology teachers are female. The main motives are the students’ fondness for biology and the desire to work with children. Students (regardless of which study programme they select) have fairly similar views on teaching biology. They believe that teachers should introduce practical work in the classroom, have good relationships with students, and are experts in their field (biology). Students in general did not provide innovative ideas about teaching methods which would not be boring or uninteresting. Their ideas reflect their own experience of teachers, which is why it is important that they are included in work with pupils as early as possible. In this way they can gain their own direct experience of teaching, which helps them to build their own unique idea of what a biology teacher should be. Also highly qualified inservice teachers (mentors) should take part in education of future biology teachers. Inservice teachers could according to functioning of future teachers’ in the classroom propose to university teacher trainers what knowledge do those future teachers lack and should gain in a faculty setting. On the basis of this information introductory science courses could be better accommodated to the needs of future teachers.

Keywords

student science teacher, teacher’s qualities, good biology teacher

Abstract

Education for Sustainable development (ESD) is an important strategy in achieving environmental improvement. Educators, such us biology teachers, have an important role to play. This article explores biology teachers’ conceptions and ideas about nature and environment, two basic conceptions in ESD. The study involved 105 biology teachers working in primary schools in Slovenia. The participating biology teachers completed a word association questionnaire. The analyses of the data show that the dominant conception of biology teachers concerning nature is biophysical. Nature is seen as non-human environment used by humans only as place of sport, recreation, beauty, quietness and rest. Dominant dimensions of environment are biophysical dimension, dimension of destruction and technostructure dimension. Environment is seen as place more dominated by human activities, infrastructure and consequences of pollution and degradation. Some similarities in teachers’ conception of nature and environment indicate conceptual confusion. Some teachers obviously think that the concept of environment is identical with that of nature.

Keywords

environment, nature, biology teacher, concepts, Education for Sustainable Development

Abstract

Biochemical biomarkers, e.g. enzyme activities, have been traditionally considered a very sensitive and specific tool to characterize the hazard of pollutants to organisms. Among them, considerable attention was given to antioxidant enzymes catalase and glutathione S-transferase, which respond to changes in the quantity of reactive oxygen species. In the present study, the two enzymes were assessed in terrestrial isopods Porcellio scaber acutely (3 days) exposed to redox active copper and compared to their whole-organism responses, such as feeding, weight change and survival. The animals were fed with copper contaminated food for 3 days and afterwards for another 3 and 6 days with uncontaminated food. In contrast to expectations, no changes of antioxidant enzymes were found throughout the experiment, while feeding parameters were already decreased after 3 days of exposure at the highest exposure concentration 5000 µg/g dry food. The concentrations tested were not acutely lethal for isopods and did not affect their weight change. These findings imply that biochemical biomarkers in some cases are not a fast and sensitive measure to characterise the hazard of chemicals. The observed finding is probably the result of interplay between a very short time of exposure and the type of chemical chosen. Namely, a special relationship exists between isopods and copper, since it is an essential element for P. scaber. It is recommended that more data on the relationship between lower and higher-level biomarkers in isopods after different exposure periods is needed and this knowledge will increase their relevance in future studies on the hazard of new emerging contaminants.

Keywords

antioxidant enzymes, biomarker; catalase; environmental risk assessment; glutathione S-transferase; hazard, Porcellio scaber